Process for heating and bending pipes.



PATENTED APR. 28, 1908.

w. L. BROWN. PROCESS FOR HEATING'AND-BENDING PIPES.

NHHMHUGMM u 1 n APPLICATIOH'IILED NOV. 7, 1904.

WITNESSES:

with my device and UNITED STATES PATENT OFFICE.

WILLARD 3. BROWN, OF TOLEDO, OHIO, ASSIGNOR TO THE SHAW-KENDALL ENGINEERING COMPANY, OF TOLEDO, OHIO.

raocnss :son HEATING mm BINDING PIPES.

\- Bpecification of Letters Patent.

Patented April 2a, 1908.

Application filed Rovcmber 7, 1904. Serial No. 231,833.

To all wlmnr it may concern:

Be it known that I, WILLARD L. Bnowx, a citizen of the United States, residing at T0- ledo, in the county of Lucas and State of Ohio, have invented a certain new and useful Process for Heating and Bending Pipes;'and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the some, reference being had to the accompanying drawings, and to the. letters and figures of reference marked thereon, which form a partof this specification.

My invention is designed to furnish a process and apparatus for bending metal pipes,

especially those e? the larger sizes, which shall overcome tln difficulties encountered in this industry in the use'of the methods and im lemenls heretofore employed.

leretofore, in bending pipes, the part to be bent has been heated by means of an external i ire, usually in a forge, the heating and bending taking place alternately as the ipe is slowly bent, step by ste to the required angle. My method of hen ing pip s consists in applying Fire, at the proper point. to the interior of the to be bent, and O1; to the outer-or lonzfer side of the band so. that the metal on the Finger side of the bend will readily yield smoothly and evenly, and so that the metal in the inner or shorter side of the bend will not buckle or crim;.-.

In practicing my process I employ an apparatus illustrated in the accompanying drawings in which- Figure 1 is a side-elevation of 12 showing the same, partly in dott position for operation in connec". pipe that is partly bent; Fig. 2, a. sideelovation, partly in central vertical section, showing one form of burner used in connection process; Fig. 3, an endview of a modified form of the same; Fig. 4, a side-elevation of said modified form, partly in central vertical sectional elevation, and Fig. 5, a central sectional elevation of a preferred form of the device for mixing the air and as in proper proportions as they are su pfied to the burner.

'ke numerals indicate like parts throughout the. drawings.

In the drawings, 1 is a flexible hose leading from a su ply of liquid or gaseous fuel. 2 is an air-libse. These two lengths of hose y device,

Y a cap or cover may be screwed onto t are, provided with suitable valves or other devices, not shown in the dra for regulating the flow and pressure tnerein. These valves and re ating mechanisms will be understood wit out further illustra- 50 tion or description. The fuel hose and the air-hose discharge rcspectivcl into a short length of pipe, 1 and 2, both leading into a single straight pipe 3 of suitable length and light enough to be easily handled man- 5. ually. Upon the end of this pipe is ahollow cylinder 4, formed preferably of cast iron and of slightly less external diameter than the .bore of the pipe to be bent. This cylinder,

at one, end, is axially mounted upon, and the 79 hollow of the c lindcr is in communication with pipe 3. T e opposite end of the cylinder is closed. The wall of the cylinder -is perforated as at 5. The perforations do not extend entirely around t e cylinder, one of its sides being imperforate. The cylinder may be cast integral as shownin Fig. 4, or may be cast with one or both ends 0 n and e open end of the cylinder as illustrated in Fig. 2. so In the large sizes the cylinder should, preferably, be provided with legs 6 which support the cylinder in roper relation to the ipe and afford stabHity to' the cylinder w hen within the pipe to be heated and bent.

My process is performed and the operation of my device is as follows: The parts being assembled as above described, the gas be' admitted through hose 1 and air through hose 2, in proper proportions and under proper pressure, the combustible -mixture ows through the pipe 3 into the perforated cylinder 4. The gases is from the perforations are first lighted and the burner, which now bums like a torch, is then thrust into the pi e to the point where the bend is to begin, tl ie pipe 3 serving as a handle for the manipulation of the burner. In inserting the perforated cylinder into the pipe, that side which is imperforate is placed next to the side of the pipe which is to form the inner side of the bend, while the perforated side of the cylinder, from which the flames are projected, is laced next to the side of the pipe which is to orm the outer or longer side of the bend. In a short time the walls and the ends of the perforated cylind r become quite hot and t e flame which p to this time has burned in jets outside the a ertures in the cylinder, now, suddenly,'.wi la pipes or bars m the ending process.

report, passes through the perforations to the interior of the cylinder. The cylinder being protected b the surrounding pipe from too rapid ra iation now becomes extremely hot and forms a retort in which the gases become superheated and from each of the holes in the wall of the cylinder issues a pale blue flame, almost invisible and of extremely high.temperature. As soon as this intensely hot flame begins to issue from the apertures in the cylinder the pipe rapidly becomes heated to a sufiicient degree to permit its deflection to any desired angle upon any desired curve by any ofthe usual methods employed for placin lateral strains u in e pipe being sufiiciently bent at one point, the

ot retort is slightly withdrawn and now an adjoining ortion of the inclosing pipe is heated an bent. Thus the heating and bending continues until the pipe has been given t e proper and desired curve.

In practice it is foun l that tubes bent according to my method are smooth and that there is a total absence of creases and buckles which are found in pipes bent by the ordinary process in which the pipe is heated externa y around its entire circumference. Since with my method it is unnecessary to return the ipe several times to the forge to be reheat during the bending operation,'

seepse exactly the right spot in the pipe, the great it 1. The process of bending pipes whichconsists in applying heat from an to the intenor of the ipe to be bent on the side which is to form t e longer side of the bend, and

then subjecting the pipe to lateral strains at opposite sides of the heated portion.

2. In the process of bending pipes, the ste s-which consist in an plying a fluidal iue. to a burner introduce into the ipe to be bent, and consuming the fuel within the pipe at the point where the bend is to take place and then subjecting the pipe to lateral strain at opposite sides of the heated portion.

3. The herein described improvement in the art of bending pipes, which consists in the application of heat directl to the inner surface of the wall of the pi e y means of a burner, and then bending t e pipe while the same is subjected to the heating medium, substantially as specified.

In testimony whereof I affix my signature in presence of two witnesses.

WILLARD L. BROWN;

Witnesses and since by my method the heat may be directly applied, without intermission, at.

CLEM V. WAGNER, ALMON I'IALL. 

